Rotary pulp screen



1932. J. STADLER ROTARY PULP SCREEN 3 Sheets-Sheet 1 Filed Jan. 2, 1930Feb. 2, 1932. J. STADLER 1,843,791

ROTARY PULP SCREEN Filed Jan. 2, 1930 5 Sheets-Sheet 2 1 INVENTOR 4?JOHN STQWLER ATTORNEYS F). 2, 1932. J, s E 1,843,791

ROTARY PULP SCREEN Fild Jan. 2, 1950 5 sheets -Sheet 3 54: [I b m? 6055/ o o INVENTOR JOHN STADLEH ATTORNEYS Patented Feb. 2, 1932 JOHN:STADLER51OF"MON P WW OFFICE CEREAL;- QUEBEC, CANADA" RotrARY PULPseminar Application-V fii'edimiiiar 2, 1930. Serial 1%.: 418,048.

g This invention relates to new and useful improvements in pulpscreening devices and the object of: the invention is to provide acombined knotter: and coarse screening j 'de cvice having comparativelylarge. inlet and discharge openings so that'there" is; noohst'ruction'to impedethe movement of the pulp throughthe screen-.

Another object of the g videa "combined'knotter and coarse screen",

thedriving; andithe supporting mechanism for 1 which are positiiime'dabove the level of the stockon'which'thescreen is operating.

According to y invention providea, screen which'corisists of'aperforated cylinder with. a free inlet opening ationeend. This endis'provided with-wring which is supporte'donits internal surface byaplurality ofrollers which are "positioned abovethe level of the Istock'gin' the screen? :The outlet is' provided with a casting halvingspaced arms which are radially disposedto 'a pivot support onsuitable-hearings so that there is substantially no obstruction oftheilow'erhalf ofth'e cylindrical screen. The screenis rotate'd by'mechanism positioned "above'fthe level of the stock inthe'screen. "Aninternal shower" pipeof large diameter" is cantilevered from iandsupported by thG' TIllGtfCQSt-r ing permits theuse 0i shower water atlow". pressure-in large quantities iso that Y the tailingsare free'fromfinefiibr'es. rt-suitable form" of bafli e is spiralled around 5 theinner: surfaceof the screen to provide a :fi'z'red path 5 along which'the'material to be screenedor clarified is caused to'travel at avrateofspeed predetermined to give the best'results, ac-

cord-ing to'the character of'rna'terial being treated; This bafllema'ybe'of uniform or irregular. pitch, depending upon the character of thematerial 'to be screened. :1 In'the' drawings which illustrate mvention; I V Figure 1 isja part sectional plan view of the-screen.

Figure Qisan endview of the screenshown inFigurel;

Figure 3 is EBfSBCtl screen.

invention is to proonal side elevation ofthe Figure 4 is an end view'ofthe inletlook ing in" the directi0n'44 of Figure 3;

1 view showing. a modified drive] mechanism applied to the'outletjendof'thescreen. 7 I Figure 6 is anend' view partly in verticalsection and partlyin' elevation of the modi-f fied drive mechanism shownin Figure5;

Figure 7 is a planview ofa scraper ele ment. 4

Figure 8 isa sectional viewtaken 'alon'g'the" line 8 8 of Figure 7. p 7r Referring more particularly to the drawiin'gs, 11 designates acylindrical screen which may be provided with reinforcing means'l2fnally on a flange ring1 4'which is supported on spaced arms 15 radiatingfrom a bearing hub"l6 support 193which' is positioned abbve ithe) pm; 19is attached to or formed integral the. screen supported internally} onerim' 23 formed on a disc'24 having a huh'25i' v The "rim'has a flange 27towh'ijch'isVsecuredbyY any suitable means the roller ringr28'. The

"internalsurfacei29 of the ring "rests on the 32aiid 33"rest 'onthebearingsurfajces 34a formedin the inlet casting .or such like finedstructure. The rollers are drivenfby any suitable means; One form ofdrive is shown" in the drawingsfor illustrative purposeson'ly andconsists" of bevel toothed wheels 34 secured tothe'ends of the rollershafts and adapted to IllGSlI'WltlifbVQl" pinions 35 secured to acommon'shaft 36rotatablym-ount- A P 17 extends outwardly. from; I jthehub into a bearing 18' secured to an" end Figure 5'is afraginentary'sectional' plan The; screen at'th'e end 13-is supportedfint'eri v develofthe stock in 'the' screeningfdevice' and indicated bythe numeralQO. The end'sup-j' with the end framefll." The otherjend 220i peripheries'oi the spaced rollers 3 0"wh'ich" v are secured to shafts31 rotatably mounted" in thetbearings 32 and 33. These bearings which iscoii-nected by: any} suitable means:

separated 'fro'm' the inlet "openinwby the-wall '42Jis th'e showerwateriinletr43t e end 44 of U IOU to a vertically disposed shower waterconveying pipe, not shown. The end 45 of the inlet 48 has connectedthereto a shower pipe 46 extending into the interior of the screen andlying substantially parallel with the longitudinal axis thereof. Theshower pipe 46 is cantilevered from the inner end of the inlet castingand is closed at its free end by a cap 47. This shower pipe ispositioned above the level of the stock passing through the screen andis providedwith perforations so arranged that the shower of water isdirect ed towards the inner surface of the screen at a predeterminedangle in order to separate the fine from the coarse material and to freethe screen surface of any material that may have a tendency to adherethereto. A scraper bar 48 is supported between a pair of arms 49 andserves to prevent accumulation of coarse material at the top of theshower pipe 46. One of the arms 49 is secured to the ring 14, while theremaining arm 49 is secured to the disc 24.

It will be seen that in operation a free central opening is provided andthat it is comparatively large when compared with the types of screensat present in use. The inlet is combined with the shower pipe inlet andalso forms a support for the screen and for the driving mechanism, whichis positioned above the stock level. The outlet end is supported on acentral pivot and the entire lower half of the screen has substantiallyno obstruction which would interfere with the flow of tailingstherethrough. The screen driving mechanism and supporting means areabove the stock level so that there is no danger of same becomingaffected by the stock.

The shower pipe is cantilevered from the stock inlet and projects intothe screen and is of large dimensions permitting the use of shower waterat low pressures in large quantities which assures that the tailings arefree from fine fibres and if white shower water is "used, there is nodilution of the accepted without any further treatment.

A bafile 51 is spiralled around the inner surface of the screen 11 toprovide a fixed path of travel along which the material is caused tomove in the direction of the screen outlet. This baffle may be ofuniform or irregular pitch according to the character of material beingscreened or clarified. Ordinarily, the spiralled baffle will be ofirregular pitch so that the drier material approach-v ing the outlet endof the screen is caused to move at a rate somewhat slower than the freshmaterial entering the inlet end of the screen.

Figures 5 and 6 disclose a modified arrangement in which the drivemechanism is located at the outlet end of the screen. In thisarrangement, the screen supporting pin 52 carried by hub 16 extends intoa gear casing 53 formed integral with or secured to the end support 19.The pin 52 rotates in a bearing 54 and is provided with a relativelylarge gear wheel 55. Gear wheel 55 meshes with a similar gear wheel 56carried by a shaft 57 journalled in suitable bearings 58; shaft 57 alsocarries a worm wheel 59 meshing with a worm 60 fixed to av-erticallyextending shaft 61. The lower portion of shaft 61 is mounted in suitablebearings 62 provided with the casing 58. Shaft 61 passes upwardly, fromthe casing 53, through a vertical pipe 63, and forms part of a motor 64carried by the upper end of said pipe. The casing53 is provided with aremovable cover 58a and any suitable means may be provided formaintaining the casing supplied with an adequate amount of lubricatingoil. A portion of this oil is picked up by the sides of the gear wheel55 and delivered to a U-shaped scraper 65 provided with an oil receivinga channel 66. The channel 66 is connected by a pipe 67 to the bearing 54of gear wheel 55 and, by a pipe 68, to the upper bearing 62 of shaft 61.The lower bearing of shaft 61- and the bearings supporting shaft 57 arelocated below the level of lubricating oil contained in casing 53.

As shown to advantage in Figure 8, the inner walls of the channel 66,lying at opposite sides of the gear wheel 55, are bevelled.

to provide sharpened edges 69 by means of which the oil is scraped fromthe sides of the gear wheel 55 and deflected into the channel 66 fromwhence it flows through the pipes 67 and 68 to lubricate the previouslymentioned bearings .54 and 62. The scraper 65 may be supported in thecasing 53 by any 1 suitable form of bracket such as that indicated at70. l

Having thus fully described what I now 1,.-

conceive to be thepreferred embodiment of my invention, it will beunderstood that various modifications may be resorted to within thescope and spirit of the appended claims. 7

Having thus described my invention, what I claim is: I

1. In a screen, a perforated cylinder supported on a disc at one end andradially disposed arms at the other end, an inlet passing through thedisc, a ring mounted at the inlet end of the screen'and roller meansengaging the internal surface of the ring and the stock in the screen.

2. In a screen, a perforated cylinder, a disc supporting'one end-of thecylinder, a plurality of arms supporting the other end leaving a cleardischarge opening, a bearing from which said arms radiate, and drivingand supporting means positioned above the high level lineof the stock ormaterial passing through the screen.

3. In a screen, a perforated cylinder, a comparatively large inlet pipeat onerend of the screen, radially ext-ending arms sup-' porting theother end and forming a free exit, a hearing from which the armsradiate, a ring secured to the inlet end of the cylinder and rollersupporting means engaging with the internal surface of the ring, saidroller means being positioned above the central axis of the cylinder.

4. In a screen, a perforated cylinder, a bearing at one end, a centralhub having arms radiating therefrom and adapted to support said cylinderend, a bearing pin extending outwardly from the hub into the bearing, aninlet pipe havin a comparatively large bore, a disc rotata ly mounted onthe wall of the pipe and adapted to support the other end of thecylinder, a ring. secured to the disc, and rollers engaging with theinternal surface of the ring and adapted to support the other end of thescreen, said rollers being positioned above the central axis of thecylinder.

5. In a screen, a perforated cylinder, a

comparatively large inlet pipe, means engaging with the wall of the pipeand adapted to position said cylinder at one end, a central hub havingradiating arms adapted to sup-' port the other end of the cylinder,a-bear ing member, a pin extending from the hub into the bearing aroller race ring secured to the inlet end of the cylinder, rollersadapted to engage with the surface of the ring to support and rotatethe, cylinder, and means to rotate said screen, said rotating means being positioned above the level of the material passingthrough thescreen.

6. A cylindrical screen having comparatively large inlet'and outletopenings, a

shower pipe cantilevered from the inlet and extending into the screen, abearing adapted to support the screen at the outlet end and roller meansadapted to support said screen, said roller means being positioned abovethe central axis of the screen.

7 In a pulp screen, a perforated cylindrical member, an inlet casting atone endthere of, said inlet casting being divided to provide separatepassages for the flow of pulp into the screen and also the flow ofshower water, a disc surrounding the casting and secured to the screenfor positioning same, a hub having radiating arms adapted to support theother end, a pin extending outwardly from the hub, a bearing engagingsaid pin, a shower plpe secured to the casting and extending surface.ofzth'ecylinder, said-disc ibeing-also" l provided Wlth 'aicentra'lopening, and with"aflange extendingoutwardlynfrom saidrim, a bearingring carried by said flange, an in let? casting projecting into thecylinder" through the central openingof thejdisc, 'roll ersarranged-within the upper portion ofthe bearing ring in supportingengagementtherewith, said rollers being mounted on'bearings carried bythe'inletcastingyand means for I supporting the opposite end of the.cylinder, 93% coarse screening device including'a cylinder,.a'rcentrally apertured disc/having V a rim engaging the inlet end ofthe cylinder, a bearing ring carried by said disc, a relatively largeinlet casting projecting into the cylinder through the central openingof the disc, rollers carried upon the upper portion of said casting insupporting engagement with said bearing ring, a second bearing ringhaving an inwardly extending rim portion fitting within the opposite endof the cylinder, a

beam supported to extend transversely across the last mentioned end ofthe cylinder and means for rot-atably supporting the last mentionedbearing ring from said beam.

10. A coarse screening device including a cylinder, a bearing ringsecured to the outlet end of said cylinder, means for rotatablysupporting said ring, a disc fitted in the inlet end of the cylinder andprovided with a central opening, means for rotatably supporting saiddisc including an inlet casting projecting into the cylinder through thecentral opening of the disc, a shower pipe extending longitudinallywithin the cylinder, at scraper 1ocated close to the shower pipe andextending in parallel relation therewith, one end of said scraper beingsupported from said disc and the other end of said scraper beingsupported from the bearing ring located at the outlet end of thecylinder.

11. A coarse screening device including a screen cylinder, a bearingring having an inwardly projecting rim portion secured in the outletendof the cylinder, an end cast-- ing, a beam secured to said casting andex-' tending transversely across the outlet end of the cylinder, saidbeam being positioned above the longitudinal axis of the cylinder andsaid bearing ring being rotatably supported therefrom, a disc fitted inthe inlet end of the cylinder and provided with a relatively large s,-central opening, a suitably supported inlet casting projected into thecylinder through i the central opening of said disc, a bearing ringcarried by said disc, supporting rollers carried by said inlet castingand serving to support the last mentioned bearing ring, and means forpositively rotating one of said bearing rings toimpart a correspondingmovement to the screen cylinder.

12. A coarse screening deviceincluding a cylindrical screen member,supporting means at the outlet end of the screen member arranged toleave the lower half of said member substantially unobstructed, acentrally apertured disc closing the inlet end of the screen and formedto provide a support for said end, an inlet casting projecting into thescreen member through the central aperture of said disc, a bearing ringfixed to rotate With the inlet end of the screen member, supportingrollers journalled on the inlet casting and engaging said bearing ring,and means for imparting rotation to said screen member through themedium of said bearing ring.

In Witness whereof, I have hereunto set my hand.

JOHN STADLER.

